A high-frequency module for amplifying a microwave signal is used for a communication device, a radar device, a power transmission device, and the like. For example, in an active phased array antenna, a plurality of high-frequency modules are connected in parallel for power synthesis and beam control. There have been proposed several methods for achieving a thinner and smaller-sized array antenna device by sharing an input connector, distributing a signal to a plurality of high-frequency modules, and thereby reducing the number of coaxial connectors.
There has been proposed a method in which an insulating substrate equipped with high-frequency electronic components and an antenna substrate equipped with a plurality of antennas are arranged with a metal casing being sandwiched therebetween, these substrates are connected by one coaxial cable, and the antenna substrate performs distribution (see Patent Document 1).
There has been proposed a method in which a plurality of antennas, amplification circuits for the respective antennas, and a distribution circuit configured to distribute an RF (Radio Frequency) signal to the respective amplification circuits are integrated and implemented in a single-layer substrate or a multilayer substrate (see Patent Document 2).